Synthesis and Structure. Wiley-VCH, Singapore 2007, xi + 679 pp., hardcover, Euro 199.00, ISBN 978-0-470-82233-3.The chemistry of zeolites and related porous materials is gaining increasing importance. A large variety of such materials ranging from zeolites, microporous molecular sieves, mesoporous materials, and macroporous materials to metal-organic frameworks (MOFs) have found wide applications in industry in areas such as catalysis, ion-exchange and sorption, and other hightechnology applications.This book places a clear focus on the chemistry of zeolites and related ordered porous materials. It is an excellent research reference for solid-state chemists, materials chemists, synthetic chemists, and geochemists. The authors have extensive research experience and have accumulated a deep understanding of the field over several years. They have taken great pains to present a true state-of-the-art picture of the field of zeolites and related porous materials. Critical research results and applications, as well as more recent developments, have been incorporated in this book. The framework and the contents of the book are reflective of the effort and careful thinking invested by the authors in this project.The chemical aspects (i.e., synthesis and structure) of zeolites and related porous materials are covered over nine chapters. The tables and figures are well designed to illustrate the contents in a straightforward manner. Chapter 1 briefly introduces the evolution, development, applications, and prospects for zeolites and related ordered porous materials.Chapter 2 summarizes the structural characteristics of zeolites and related microporous materials. Structure analysis is a fundamental aspect of zeolite chemistry. Detailed understanding of the structure helps in mapping the relationship between syntheses, structures, and properties of porous materials. The abundant structural information about zeolites and related microporous materials provided in this chapter is essential for researchers seeking to obtain a good understanding of this field.Chapter 3 presents the hydrothermal and solvothermal synthesis approaches generally used for the preparation of molecular sieves and porous materials.

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Just as with crystalline enzymes, crystalline microporous inorganic catalysts. typified by zeolites, are amenable to direct, in situ X-ray (or neutron) study,", 2] a quantitative description of the local environment of the active site being obtainable from the diffraction pattern. The situation is not so straightforward with crystalline aluminophosphate-based catalysts, represented by MAPOs, where M is a divalent cation (Co, Ni, Zn, Mn, Mg etc) that isoinorphously substitutes for some of the aluminum in the framework. Framework-substitution of trialent aluminum ions by divalent ones such as Co" not only confers Brarnsted acidity upon the resulting solid---a proton, loosely attached to one of the framework oxygen atoms, is required to maintain electroneutrality-it also introduces redox b e h a~i o r . '~.~] When the Co" ion is oxidized to the Co"' state the Brernsted acidity necessarily disappears. Here, the concentration of M (in this case Co) is generally so low-seldom exceeding a few percent and often much less-that X-ray diffraction (XRD) cannot yield the desired (local) structural information. Under these circumstances. X-ray absorption spectroscopy (X-ray absorption near edge structure, XANES and extended X-ray absorption tine structure, EXAFS) is the preferred method of probing the environment of the active site, especially when it is used in combination'sl with X-ray diffraction, the principal purpose of the latter being to monitor the long-range integrity of the catalyst during the various processes of activation, deactivation and regeneration.We recently described[', 71 a family of molecular sieve catalysts in which minute amounts of cobalt ions are framework-substituted in place of aluminum ions in the open structure of a synthetic aluminum phosphate known as ALPO-18.[" These solid acid catalysts H,(Co,AI,, -x,PO,), x 50.04, efficiently convert ['] methanol to light oletins (predominantly ethylene and propylene), a process well-known[g-' I 1 to require more than modest Brnnsted acidity. Typically, at 400 "C and a weight hourly space velocity (WHSV) of 1.5, methanol is completely converted to ethylene (22.4 percent), propylene (51.2), and C, olefins, chiefly butenes, (25.6) and a trace of methane.The CoAPO-18 catalysts are synthesized hydrothermally in the presence of an organic template, N,N-diisopropylethylamine a t 150 to 180°C for three to ten days-full details are given elsewhere", 7]-the template-free samples being obtained by calcining the as-synthesized ones in gaseous oxygen at 550 "C for about one hour. Prior to use they were reduced in hydrogen at 400 "C.

A light-inducing approach has been demonstrated for the preparation of porous TiO(2) with a large number of stored electrons, which can provide an electron source for subsequent use in redox reactions and provide a spin source to achieve a new room-temperature ferromagnetic semiconductor.